1. Field of the Invention
This invention relates to electrostatography, and more particularly to an electrostatographic copier or printer for producing raised multiple color images.
2. Description Relative to the Prior Art
Apparatus for producing raised images on a suitable substrate such as a copy sheet, for example, those apparatus employing lithographic methods, do so by applying a colorless powder to wet ink on an ink printed substrate. For quality results, the powder must be applied before such ink dries. This method works satisfactorily for the production of raised single color images on such substrate, but does not work well for the production of raised multiple color images. This is because the production of two color images, for example, involves the use of a two-color press which first prints with a first wet ink of a first color, and then with a second wet ink of a second color before the colorless powder can be applied. Ordinarily, by the time of printing with the second wet ink, the first ink has already dried, thereby defeating any efforts to apply and have the colorless powder adhere to the dried first ink. There is therefore a need for methods and apparatus for efficiently producing such raised multiple color images.